you are deemed canadian resident, have to report x+y to canada,
if you live in usa less than 183 days, you are non resident, only need report y income to usa.
if you use Form 2555, you must be us citizen or resiend allian( green card) and live outside USA
330 full days during which you were present in a foreign country.
you cannot use form 2555, but you donot need roport x to usa, for canana tax , you can deducte the foreign tax credit on federal tax withhold, and check the tax trreat for social security tax and medical tax, i donot have time to check for you.